this improves load time by 20%.
We switch from shared_ptr to tools::SvRef to manage the objects
I noticed some double inheritance like this:
so to be safe I made all the ref-count-base-class inheritance
Reviewed-on: https://gerrit.libreoffice.org/57022Reviewed-by: Noel Grandin <firstname.lastname@example.org>
Tested-by: Noel Grandin <email@example.com>